With the development on technology, a person has one or more communication terminals, such as mobile phones. The communication terminals have become people's indispensable communication tools in daily life and work. Nowadays, the communication terminals, such as mobile phones, use radio waves as a medium for communication. As is well known, the radiation intensity of the radio frequency waves is greater, so that people's health will be affected and the communication quality will greatly be affected by the signal quality. Thus, the radio frequency communication technique also suffers from a number of disadvantages.